Method of making dies



Aug. 11, 1925. 1,548,896

R. L. MORGAN METHob OFMAKING DIES Filed Oct. 12, 1923 Patented Aug. 11,192 5,

mm a. xenon, or woncnsrnn, nassacnusm'rs.

mnrnonor manna mas.

Application filed October 12, 1923. Serial No. 868,082.

To all whom it may concern Be it known that I, Ranrn L. MORGAN,

a citizen of the United States residing at Worcester in the count ofWorcester and State of Massachusetts, and useful Method of Making Dies,of which the following is a specification.-

This invention relates to dies such as are commonly used in wire drawingoperations. Sucl tapered hole therein, which at its smaller end is ofthe exact size of the wire to'be, drawn. 'Such dies are sub1ect to veryse-' vere wear when in use, particularly when.

the wire is not fully cleaned ofdirt" and scale, and the dies requlrefrequent re dressing to restore them to their correct size.

It is the object of my invention to provide method -by 1 which such dies(1 may be economically;1 and accurately restored an improved to size,and by whic new dies may bemanu factured if desired. While particularlegg plicable to wire drawing dies, 1t wi understood that the invention1s not necesisarily kind of die.

For a,more complete disclosure of my. in-' drawmgs a vention I haveindicated in the form of mechanism by which my im roved method orprocess may be convenient y car-'- ried out.

Fi 1. of the drawings is a side elevation of a.( ir

op hammer, together'with certain at-.-;

tachments adapting the same to my purposes;

shown in Fig. 1;. and

Fig. 3 is an enlarged sectlonalview of a worn die before re-dressing. a

Referring to the drawings, I have indicated parts of a drop hammerof ausual commercial type, comprising a frame 10, a weight or head 11, aliftin board or bar 12 secured to the upper end 0 the weight 11, drivenrolls 13 and 14 for raising the weight, and a knee or bracket 15 forsupporting the work. All of these parts, together with suitablemechanism (not shown) for rotating the driven rolls and for moving themtoward and from each other usual construction andin themselves form nopart of my invention.

A die holder-16 is pivoted at 17 on the bracket 15 and comprises twojaws which may be held in closed ,positionby a ring 18 'aws and centersthe same ave invented a new arms 2 1- dies are made of hard metal withal other-at and the 1 limited to use with this particularin, thedrawings,

Fig. 2 is a plan view of .the die holder may be of the fitting over thehandles or extensions 19; A block 20 limits inward racket or support 15.

A mandril 21 is slidable vertically in an opening or passage in thebracket 15 and IS centrally disposed with respect to the opening 1n theholder 16. A pair of toggle 'and are mounted below the mandril 2 1,thesearms being pivoted to each formed as a portion of a bell crank having 3also a foot lever or pedal portion 25. The upper arm 22 is.

pivoted at 26 to the lower movement of the accurately onjthe a ower arm23 being of the mandriland a spring 27 tends to straighten the to 1eainst a etc in or' stud 28. When t ag p p' the tog le is broken" rawnownward.

upper face of a wire drawing die construction of the-"die" D is clearlyshown in Fig.13 which also indicates at 31 the wear [A die block 30 issecured in the lower sur- I ace of the weight or head 11 and is con,cavely' shaped to correspond to the D. The general.

e pedal 25 is depressed and the mandril id which' ta es place during thewire drawing operation. I v v aving described the mechanism shown Iwill'nowexplain my new method or process of shaping or re-dressing d1es.For this purpose, the die D is first heated until the metalis-sufiiciently softened so that-it can be re-distributed underpressure. 'The die isthen dropped over-the up-:

per end of the mandril 21, which is held In the fixed raised positionindicated in Fi 1.

The holder 16 is then clamped firmlya ut the die and the head '11 isallowed to drop upon the upper surface thereof.

Contact of the concave block 30 with the upper of'the, die D forces theheated metal downward and inward against theu per end of. the mandriland causesthe 1e to conform exactlyto the outline thereof. Outward exansion is revented- -Iby the holder 16. he mandri is them quicklywithdrawn b de the re-forme die is transferred to-asuitable cooling andhardening bath;

It is desirable that the surface of themanressing the [pedal 25, and'dril be coated with graphite ori otherlubricant before thedie is placedthereoaier. This lubricant delays the transfer of heat to the mandrilandwill also giveofi smoke and combustion gases which will 'largely preventoxidation of the die while it is bemg shaped and transferred to thecooling d and tempering bath.

It is t us seen that my improved method or process enables me toaccurately she or re-sha wire drawin and other dles with a minimumexpenditure of time and labor and with absolutely accurate and identicalresults in successive dies. Furthermore, the fact that oxidation isprevented leaves the wire drawing p smooth and in the best possi 1econdition for drawin wire.

Having t us described my invention and the advantages thereof, I do notwish to be limited to the details herein disclosed otherwise than as setforth in the claims, but what I claim is:

1.- The method of forming a die which consists in heating the die,placing an accurately sized mandril within the hole in the die, firmlcompressing the die about the mandril whi e the mandril is thuspositioned, and thereafter withdrawing said mandril.

2. The method of forming a die which consists in heating the die,placing an acemthedie messes curately sized mandril within the hole inthe is, compressin the material of the die about the mandril while themandril is thus positioned, promptly separating the die and mandril, andthereafter hardenin the die.

3. The method of forming a ie which consists in heating the die, placingan accurately sized mandril within the hole in the die, holding the diefrom radial exansion and striking the die a heavy blow in an axialdirection to force the material of the die against the mandril while themandril is thus positioned, said blow also firmly and simultaneouslycompressing said material.

4. The method of forming a die which consists in heating the die,coating an accurately sized mandril with lubricant, lacing the coatedmandril within the ho e in the die, compremin the material of the dieabout said mandril while the mandril is thus positioned, and thereafterseparating said die and mandril, the combustion of the lubricantpreventing oxidation of the die.

In testimony whereof I have hereunto affixed my signature.

RALPH L. MORGAN.

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